Unless you get lucky, you're going to have some clutch wear after turning your stick shift car over to a valet service. It is simply the way it is.
(Where can you go to learn to drive a manual transmission car anyway?Businesses that offer these lessons are scarce.)
Valet services are desperate to find workers with this skill, and they end up succumbing to hiring the workers that are available, who have no stick shift experience.
And then, when a car needs to be brought out of the garage, and its a manual, and nobody knows how to move it, the panic sets in.
Will one of them be brave enough to try to bring it out? Perhaps one of them will rise to the occasion and "go for it." Then they will be asking "What's that burning smell."
Guess what? There are valets that learn how to drive manual transmission cars by using their customer's cars. (Yes, absolutely!)
If you have a manual transmission vehicle, I strongly recommend parking it yourself.